code: def test_art1_on_real_problem(self):
      data = pd.DataFrame(lenses)
  
      encoder = preprocessing.OneHotEncoder(categories="auto")
      enc_data = encoder.fit_transform(data.values[:, 1:]).toarray()
  
      artnet = algorithms.ART1(
          step=1.5,
          rho=0.7,
          n_clusters=3,
          verbose=False,
      )
      classes = artnet.predict(enc_data)
  
      unique_classes = list(np.sort(np.unique(classes)))
      self.assertEqual(unique_classes, [0, 1, 2])
  
file_path: neupy/tests/algorithms/competitive/test_art.py
imports: import numpy
  import pandas
  from sklearn import preprocessing
  from neupy import algorithms
  from base import BaseTestCase
label_desc: Use image node_id 3 for calling the ARTTestCase obj's underlying member method code with example usage: obj.test_art1_on_real_problem() without return types